CN101375798B - CT imaging system and method with second tube/detector patching - Google Patents

Abstract

The present invention relates to a CT imaging system comprising a second ray tube/detector and a method thereof. The CT imaging system (10) includes a rotatable gantry (12) having an opening (48) to receive an object (22) to be scanned, a first x-ray emission source (90, 190) attached to the rotatable gantry (12) and configured to emit x-rays toward the object (22), and a second x-ray emission source (92, 192) attached to the rotatable gantry (12) and configured to emit x-rays toward the object (22). A first detector (100, 200) is configured to receive x-rays that emit from the first x-ray emission source (90, 190), and a second detector (106, 206) configured to receive x-rays that emit from the second x-ray emission source (92, 192). A first portion of the first detector (100, 200) is configured to operate in an integration mode and a first portion of the second detector (106, 220) is configured to operate in at least a photon-counting mode.

Description

Translated fromChinese

具有第二射线管/检测器修补的CT成像系统和方法CT imaging system and method with second tube/detector patching

技术领域technical field

本发明一般涉及诊断成像，更特别涉及校正在光子计数中发生的饱和数据的方法和可配置模式检测器。The present invention relates generally to diagnostic imaging, and more particularly to methods and configurable pattern detectors for correcting saturation data that occur in photon counting.

背景技术Background technique

通常，在计算断层扫描(CT)成像系统中，x射线源向物体或目标，诸如病人或一件行李发出扇形射线束。下文中，术语“物体”和“目标”应当包括能够被成像的任何东西。射线束在被物体衰减之后，撞击辐射检测器阵列。在辐射器处检测的经过衰减的射线束辐射的强度通常取决于物体对x射线束的衰减。检测器阵列中每个检测器元件产生单独的电信号，指示每个检测器元件接收的经过衰减的射线束。电信号被传送到数据处理系统进行分析，最终生成图像。Typically, in computed tomography (CT) imaging systems, an x-ray source emits a fan beam at an object or target, such as a patient or a piece of luggage. Hereinafter, the terms "object" and "target" shall include anything capable of being imaged. After being attenuated by the object, the beam of radiation strikes the radiation detector array. The intensity of the attenuated beam radiation detected at the radiator typically depends on the attenuation of the x-ray beam by the object. Each detector element in the detector array generates a separate electrical signal indicative of the attenuated beam of radiation received by each detector element. The electrical signals are sent to a data processing system for analysis, which ultimately produces an image.

通常，x射线源和检测器阵列绕着成像平面中的台架旋转并围绕物体。X射线源通常包括x射线管，在焦点处发出x射线束。X射线检测器通常包括用于校准在检测器处接收的x射线束的准直器，靠近准直器的、用于将x射线转换成光能的闪烁体，以及用于接收邻近的闪烁体发出的光能并从中产生电信号的光电二极管。Typically, the x-ray source and detector array rotate around the gantry in the imaging plane and surround the object. An x-ray source typically includes an x-ray tube emitting a beam of x-rays at a focal point. X-ray detectors typically include a collimator for collimating the x-ray beam received at the detector, a scintillator adjacent to the collimator for converting the x-rays into light energy, and a scintillator for receiving adjacent A photodiode that emits light energy and generates an electrical signal from it.

通常，闪烁体阵列中的每个闪烁体将x射线转换成光能。每个闪烁体将光能放到与其相邻的光电二极管。每个光电二极管检测光能并生成对应的电信号。光电二极管的输出被接着传送到数据处理系统用于图像重构。Typically, each scintillator in the scintillator array converts x-rays into light energy. Each scintillator puts light energy into its adjacent photodiode. Each photodiode detects light energy and generates a corresponding electrical signal. The output of the photodiode is then sent to a data processing system for image reconstruction.

在大部分计算断层扫描(CT)成像系统中，x射线源和检测器阵列绕包围成像体积的台架旋转并围绕目标物体。X射线源通常包括x射线管，从阳极焦点发出作为扇形或者锥形射线束的x射线。X射线检测器组件通常包括用于减少散射x射线光子到达检测器的准直器，靠近准直器的、用于将x射线转换成光能的闪烁体，以及靠近闪烁体的、用于接收光能并从中产生电信号的光电二极管。通常，闪烁体阵列中的每个闪烁体将x射线转换成光能。每个光电二极管检测光能并生成对应的电信号。光电二极管的输出被接着传送到数据获取系统，并接着到用于图像重构的处理系统。In most computed tomography (CT) imaging systems, an x-ray source and detector array rotate about a gantry that encloses an imaging volume and surrounds an object of interest. An x-ray source typically comprises an x-ray tube emitting x-rays as a fan or cone beam from an anode focus. X-ray detector assemblies typically include a collimator to reduce scattered x-ray photons from reaching the detector, a scintillator near the collimator to convert the x-rays into light energy, and a scintillator near the scintillator to receive A photodiode that generates light energy and generates an electrical signal from it. Typically, each scintillator in the scintillator array converts x-rays into light energy. Each photodiode detects light energy and generates a corresponding electrical signal. The output of the photodiode is then sent to a data acquisition system and then to a processing system for image reconstruction.

现有CT成像系统利用的检测器将在一段时间上合计的x射线光子能量转换成电流信号，接着被测量并最终被数字化。这种检测器的一个缺陷是它们不能提供关于检测的光子的能量和入射通量率的独立数据或反馈。即，现有CT检测器具有的闪烁体部件和光电二极管部件中，闪烁体部件在接收到x射线光子时发光，光电二极管检测闪烁体部件的发光，并提供作为多个入射x射线光子的强度和能量的函数的积分的电流信号。尽管普遍认同如果没有现有CT检测器设计实现的进步，CT成像将不是一种可行的诊断成像工具，这些合计检测器的一个缺陷是它们不能提供能量可辨别数据，或者对给定的检测器元件或像素实际接收的光子的数量进行计数和/或测量它们的能量。从而，最近的检测器开发已经包括能量可辨别检测器的设计，其可以提供光子计数和/或能量辨别反馈。在这个方面，可以使该检测器工作在x射线计数模式，每次x射线事件的能量测量模式，或者两者。Detectors utilized by existing CT imaging systems convert x-ray photon energy summed over a period of time into electrical current signals, which are then measured and eventually digitized. A drawback of such detectors is that they cannot provide independent data or feedback on the energy and incident flux rate of the detected photons. That is, in the scintillator unit and the photodiode unit that the conventional CT detector has, the scintillator unit emits light when receiving x-ray photons, and the photodiode detects the light emission of the scintillator unit, and provides the intensity as a plurality of incident x-ray photons. and the integrated current signal as a function of energy. While there is general agreement that CT imaging would not be a viable diagnostic imaging tool without the advances achieved by existing CT detector designs, a drawback of these aggregate detectors is that they do not provide energy-discriminative data, or The number of photons actually received by the element or pixel is counted and/or their energy is measured. Thus, recent detector development has included the design of energy discriminative detectors, which can provide photon counting and/or energy discriminative feedback. In this regard, the detector can be operated in x-ray count mode, energy measurement per x-ray event mode, or both.

这些能量可辨别检测器不仅能够进行x射线计数，还能提供检测到的每个x射线的能量等级的测量。尽管多种材料可以用于包括闪烁体和光电二极管的能量辨别检测器的构造，已经显示具有诸如非晶锗或者碲锌镉的，直接将x射线光子转换成电荷的光电导体的直接转换检测器是在优选的材料之中。光子计数检测器的一个缺陷是这些类型的检测器具有有限的计数率，并且很难覆盖包含非常高x射线光子通量率的宽广的动态范围，而非常高x射线光子通量率是现有CT系统通常碰到。一般，需要1000000到1的CT检测器动态范围，以便正确应对CT成像中碰到的光子通量率的可能变化。在现在可用的快速扫描仪中，当扫描域中没有目标时碰到超过10⁸光子/mm²/秒以上的x射线通量并不少见，而同一系统需要计数能够穿过大型目标的中心的仅仅几十个光子。These energy-discriminative detectors are not only capable of counting x-rays, but also provide a measure of the energy level of each x-ray detected. Although a variety of materials can be used for the construction of energy-discriminating detectors including scintillators and photodiodes, direct conversion detectors have been shown with photoconductors such as amorphous germanium or cadmium zinc telluride, which directly convert x-ray photons into charge. is among the preferred materials. A drawback of photon-counting detectors is that these types of detectors have limited count rates and it is difficult to cover the wide dynamic range encompassing the very high x-ray photon flux rates that are currently CT systems are commonly encountered. Typically, a CT detector dynamic range of 1000000 to 1 is required in order to properly account for possible variations in photon flux rates encountered in CT imaging. In today's available fast scanners, it is not uncommon to encounter x-ray fluxes above¹⁰⁸ photons/^mm2 /sec when there is no target in the scan field, and the same system needs to count particles capable of passing through the center of a large target Just a few dozen photons.

非常高的x射线光子通量最终导致检测器饱和。即，这些检测器通常在相对低的x射线通量水平饱和。这种饱和可以在小的物体厚度被夹在检测器和辐射源或x射线管之间的检测器位置处发生。已经表明这些饱和区域对应于投影到检测器阵列的物体的宽度附近或者之外的低物体厚度的通路。在很多情况下，物体在对x射线通量的衰减以及随后的对检测器阵列的入射强度的影响上或多或少是圆柱形的。在此情况下，饱和区域表示检测器阵列的末端处两个不相接的区域。在其它不太典型但是并不少见的情况中，饱和在其它位置发生，并且位于检测器上多于两个不相接的区域。在圆柱形物体的情况下，阵列边缘的饱和可以通过在物体和x射线源之间安放蝶形滤片(bowtie filter)而减少。通常，滤片被构造为以使得总衰减，滤片和物体在检测器阵列上均衡的方式匹配物体的形状。从而入射到检测器的通量在阵列上相对均匀，而不导致饱和。然而，可能成为问题的是，在物体群体明显不均匀并且在形状上不完全是圆柱形，也不中心位于射线束的情况下该蝶形滤片可能不是最优的。在这种情况下，也可能出现一个或多个不相接的饱和区域或者过度过滤x射线通量并不必要地产生非常低通量的区域。投影中低的x射线通量导致信息内容减少，这最终会在重构的物体图像中助长不想要的噪声。Very high x-ray photon fluxes eventually lead to detector saturation. That is, these detectors typically saturate at relatively low x-ray flux levels. This saturation can occur at detector locations where small object thicknesses are sandwiched between the detector and the radiation source or x-ray tube. It has been shown that these saturation regions correspond to passages of low object thickness projected onto the detector array near or beyond the width of the object. In many cases, objects are more or less cylindrical in their attenuation of the x-ray flux and consequent impact on the incident intensity of the detector array. In this case, the saturation region represents two disjoint regions at the ends of the detector array. In other, less typical but not uncommon cases, saturation occurs elsewhere and in more than two disjoint regions on the detector. In the case of cylindrical objects, saturation at the edge of the array can be reduced by placing a bowtie filter between the object and the x-ray source. Typically, the filter is configured to match the shape of the object in such a way that the total attenuation, filter and object are balanced across the detector array. The flux incident on the detector is thus relatively uniform across the array without causing saturation. However, it can be problematic that the butterfly filter may not be optimal in cases where the population of objects is significantly inhomogeneous and not perfectly cylindrical in shape, nor centered in the beam. In this case, one or more disjoint saturation regions or regions that overfilter the x-ray flux and unnecessarily produce very low flux may also occur. Low x-ray flux in the projection leads to reduced information content, which ultimately contributes to unwanted noise in the reconstructed object image.

已经提出多种技术来解决检测器任何部分的饱和。这些技术包括在检测器阵列的宽度上保持低x射线通量，例如，通过在扫描过程中调制射线管的电流或者x射线电压。然而，这种解决方案使扫描时间增加。即，存在图像的获取时间与额定通量成比例增加的不利之处，该额定通量是获取满足图像质量要求的特定数量的x射线所需的。Various techniques have been proposed to address saturation of any part of the detector. These techniques include keeping the x-ray flux low across the width of the detector array, for example, by modulating the tube current or x-ray voltage during scanning. However, this solution increases the scan time. That is, there is the disadvantage that the acquisition time of an image increases in proportion to the nominal fluence required to acquire a certain number of x-rays satisfying image quality requirements.

此外，已经开发了可配置模式检测器，能够工作在积分或者光子计数模式，其中数据处理方法在检测器的高通量部分从光子计数模式变化到积分模式。然而，对于可配置模式检测器，可能不能获得完整的动态范围，仍会发生饱和。In addition, configurable mode detectors have been developed, capable of operating in either integrating or photon-counting modes, where the data processing method changes from photon-counting to integrating modes in the high-throughput part of the detector. However, with configurable pattern detectors, the full dynamic range may not be available and saturation will still occur.

已经构建了具有多源/检测器子系统的系统，以便改进时间分辨率。然而，这些系统既不包括光子计数能力，也不具有用来自不饱和检测器子系统的数据重建(re-bin)或同时校正一个检测器子系统中的饱和数据的能力。Systems with multiple source/detector subsystems have been built in order to improve temporal resolution. However, these systems neither include photon counting capabilities nor the ability to re-bin or simultaneously correct saturated data in one detector subsystem with data from unsaturated detector subsystems.

因此，期望有能够校正在光子计数中发生的饱和数据的系统和方法，以及在多源/检测器CT系统中使用来自非饱和检测器的数据的可配置模式检测器。Therefore, it is desirable to have systems and methods that can correct for saturation data that occurs in photon counting, as well as configurable pattern detectors that use data from non-saturated detectors in multi-source/detector CT systems.

发明内容Contents of the invention

本发明涉及校正在光子计数中发生的饱和数据的方法和设备，以及在多源/检测器CT系统中使用来自非饱和检测器的数据的可配置模式检测器。The present invention relates to methods and apparatus for correcting saturation data that occurs in photon counting, and to configurable pattern detectors using data from non-saturated detectors in multi-source/detector CT systems.

揭示了具有第二射线管/检测器数据修补的光谱CT系统。CT检测器包括半导体层，该半导体层具有附着到其上的多个像素化的阳极。该CT检测器不仅支持X射线光子计数，还支持能量测量或标记以及能量积分。结果，本发明支持解剖学细节以及组织特征信息两者的获得。在此方面，能量辨别信息或数据可以用于减少射线束硬化之类的效应。此外，这些检测器支持组织辨别数据的获取，因而提供指示疾病或者其它反常的诊断信息。这些检测器也可以用于通过使用最优能量加权增强碘和钙(以及其它高原子或材料)的对比度，检测、测量和特征化可以注入到物体中的材料，诸如造影剂和其它专用材料。造影剂例如可以包括注入血流中的碘供更好的观察。A spectral CT system with second tube/detector data inpainting is disclosed. A CT detector includes a semiconductor layer having a plurality of pixelated anodes attached thereto. This CT detector supports not only X-ray photon counting but also energy measurement or marking and energy integration. As a result, the present invention supports the acquisition of both anatomical details as well as tissue characteristic information. In this regard, energy discriminative information or data may be used to reduce effects such as beam hardening. In addition, these detectors support the acquisition of tissue-discriminating data, thus providing diagnostic information indicative of disease or other abnormalities. These detectors can also be used to detect, measure and characterize materials that can be injected into objects, such as contrast agents and other specialty materials, by enhancing the contrast of iodine and calcium (and other high atoms or materials) using optimal energy weighting. Contrast agents may include, for example, iodine injected into the bloodstream for better visualization.

根据本发明的一个方面，一种CT成像系统包括可旋转台架，具有接收要扫描的目标物体的开口；第一x射线发射源，连接到所述可旋转台架并且配置为朝目标物体发射x射线；以及第二x射线发射源，连接到所述可旋转台架并且配置为朝目标物体发射x射线。第一检测器配置为接收从第一x射线发射源发射的x射线，第二检测器配置为接收从第二x射线发射源发射的x射线。第一检测器的第一部分配置为工作在积分模式，第二检测器的第一部分配置为工作在至少光子计数模式。According to one aspect of the present invention, a CT imaging system includes a rotatable gantry having an opening for receiving a target object to be scanned; a first x-ray emitting source connected to the rotatable gantry and configured to emit x-rays; and a second x-ray emitting source coupled to the rotatable gantry and configured to emit x-rays toward a target object. The first detector is configured to receive x-rays emitted from the first x-ray emitting source and the second detector is configured to receive x-rays emitted from the second x-ray emitting source. A first portion of the first detector is configured to operate in an integrating mode and a first portion of the second detector is configured to operate in at least a photon counting mode.

根据本发明的另一方面，一种x射线成像的方法包括，在第一检测器阵列的第一部分中接收x射线，所述x射线从第一x射线源发出穿过成像区域的至少一部分，以及在第二检测器阵列的第一部分中接收x射线，所述x射线从第二x射线源发出穿过成像区域的至少一部分。该方法还包括，以积分模式操作第一检测器阵列的第一部分，以从接收的x射线生成第一组数据，以光子计数模式操作第二检测器阵列的第一部分，以从接收的x射线生成第二组数据，以及使用第一和第二组数据生成图像。According to another aspect of the invention, a method of x-ray imaging includes receiving x-rays in a first portion of a first detector array, the x-rays being emitted from a first x-ray source through at least a portion of an imaging region, and receiving x-rays in the first portion of the second detector array, the x-rays being emitted from the second x-ray source through at least a portion of the imaging region. The method also includes operating a first portion of the first detector array in an integrating mode to generate a first set of data from received x-rays and operating a first portion of a second detector array in a photon counting mode to generate a first set of data from received x-rays A second set of data is generated, and an image is generated using the first and second sets of data.

根据本发明的还有另一方面，一种CT成像系统包括台架，配置为绕目标物体旋转；以及一对源，连接到所述台架并配置为朝目标物体发出高频电磁辐射。第一检测器阵列模块配置为接收从该对源的第一源发出并穿过目标物体的高频电磁辐射，第二检测器阵列模块配置为接收从该对源的第二源发出并穿过目标物体的高频电磁辐射。第一检测器阵列模块配置为工作在至少积分模式，第二检测器阵列模块配置为工作在至少光子计数模式。According to yet another aspect of the present invention, a CT imaging system includes a gantry configured to rotate about a target object; and a pair of sources connected to the gantry and configured to emit high frequency electromagnetic radiation toward the target object. The first detector array module is configured to receive high-frequency electromagnetic radiation emanating from the first source of the pair of sources and passing through the target object, and the second detector array module is configured to receive high-frequency electromagnetic radiation emanating from the second source of the pair of sources and passing through the target object. High-frequency electromagnetic radiation from a target object. The first detector array module is configured to work in at least the integration mode, and the second detector array module is configured to work in at least the photon counting mode.

本发明的各种其它特征和优点将从下面的详细描述和附图变得清楚。Various other features and advantages of the present invention will become apparent from the following detailed description and accompanying drawings.

附图说明Description of drawings

附图示出目前意图实现本发明的一个优选实施例。The drawings show a presently preferred embodiment intended to carry out the invention.

附图中：In the attached picture:

图1是CT成像系统的绘图。Figure 1 is a drawing of a CT imaging system.

图2是图1所示系统的示意框图。FIG. 2 is a schematic block diagram of the system shown in FIG. 1 .

图3是CT系统检测器阵列的一个实施例的透视图。Figure 3 is a perspective view of one embodiment of a CT system detector array.

图4是检测器的一个实施例的透视图。Figure 4 is a perspective view of one embodiment of a detector.

图5是直接转换检测器的一个实施例的侧视图。Figure 5 is a side view of one embodiment of a direct conversion detector.

图6示出根据本发明一实施例具有两个源和两个检测器阵列的台架。Figure 6 shows a gantry with two source and two detector arrays according to an embodiment of the invention.

图7示出根据本发明另一实施例具有两个源和两个检测器阵列的台架。Figure 7 shows a gantry with two source and two detector arrays according to another embodiment of the invention.

图8是与非侵入包裹检查系统一起使用的CT系统的绘图。8 is a drawing of a CT system used with a non-invasive package inspection system.

具体实施方式Detailed ways

诊断设备包括x射线系统、磁共振(MR)系统、超声系统、计算断层扫描(CT)系统、正电子发射断层扫描(PET)系统、超声、核医疗学和其它类型的成像系统。X射线源的应用包括成像、体格检查、安全、以及工业检查应用。然而，在此，本领域技术人员将见到一个适用于与单层或其它多层配置一起使用的实现方案。以及，一个可以用来检测和转换x射线的实现方案。本领域技术人员还将进一步见到一个可以用来检测和转换其它高频电磁能量的实现方案。一个可用于“第三代”CT扫描仪和/或其它CT系统的实现方案。Diagnostic equipment includes x-ray systems, magnetic resonance (MR) systems, ultrasound systems, computed tomography (CT) systems, positron emission tomography (PET) systems, ultrasound, nuclear medicine, and other types of imaging systems. Applications for x-ray sources include imaging, medical examination, security, and industrial inspection applications. Here, however, those skilled in the art will see an implementation suitable for use with single-layer or other multi-layer configurations. And, an implementation that can be used to detect and convert x-rays. Those skilled in the art will further see an implementation that can be used to detect and convert other high frequency electromagnetic energies. An implementation that can be used in "third generation" CT scanners and/or other CT systems.

参考六十四层计算断层扫描(CT)系统描述本发明的工作环境。然而，本领域技术人员应理解本发明同样适用于与其它多层配置一起使用的场合。此外，还将参照x射线的检测和转换描述本发明。然而，本领域技术人员将进一步认识到本发明也同样适用于其它高频电磁能量的检测和转换。本发明将参照“第三代”CT扫描仪描述，但是同样适用于其它CT系统。The operating environment of the present invention is described with reference to a sixty-four slice computed tomography (CT) system. However, those skilled in the art will appreciate that the present invention is equally applicable for use with other multilayer configurations. Furthermore, the invention will be described with reference to the detection and conversion of x-rays. However, those skilled in the art will further recognize that the present invention is equally applicable to the detection and conversion of other high frequency electromagnetic energies. The invention will be described with reference to "third generation" CT scanners, but is equally applicable to other CT systems.

参考图1，示出了计算断层扫描(CT)系统10，包括表示“第三代”CT扫描仪的台架12。台架12具有x射线源14，朝台架12的相对侧上的检测器组件或准直器18投射x射线束16。现在参考图2，检测器组件18由多个检测器20和数据获取系统(DAS)32构成。该多个检测器20感应穿过医疗病人22的投射的x射线，DAS32将数据转换成数字信号供后续处理。每个检测器20产生表示撞击的射线束并就此而随着穿过病人而被衰减的射线束的强度的模拟电信号。在获取x射线投射数据的扫描过程中，台架12和安装于其上的部件绕旋转中心24旋转。Referring to FIG. 1 , a computed tomography (CT)system 10 is shown including agantry 12 representing a "third generation" CT scanner. Thegantry 12 has anx-ray source 14 that projects anx-ray beam 16 towards a detector assembly orcollimator 18 on the opposite side of thegantry 12 . Referring now to FIG. 2 , thedetector assembly 18 is comprised of a plurality ofdetectors 20 and a data acquisition system (DAS) 32 . The plurality ofdetectors 20 sense projected x-rays passing through a medical patient 22, and theDAS 32 converts the data into digital signals for subsequent processing. Eachdetector 20 produces an analog electrical signal representative of the intensity of the impinging beam and, thereby, the beam attenuated as it passes through the patient. During a scan to acquire x-ray projection data, thegantry 12 and components mounted thereon rotate about a center ofrotation 24 .

台架12的旋转和x射线源14的工作由CT系统10的控制机构26管理。控制机构26包括x射线控制器28，提供功率和定时信号给x射线源14以及台架电动机控制器30，控制台架12的旋转速度和位置。图像重构器34从DAS32接收采样并数字化的x射线数据并进行高速重构。将经过重构的图像作为输入施加到计算机36，计算机36在大容量存储装置38中存储该图像。The rotation of thegantry 12 and the operation of thex-ray source 14 are managed by acontrol mechanism 26 of theCT system 10 .Control mechanism 26 includes anx-ray controller 28 that provides power and timing signals to x-raysource 14 and agantry motor controller 30 that controls the rotational speed and position ofgantry 12 .Image reconstructor 34 receives sampled and digitized x-ray data fromDAS 32 and performs high speed reconstruction. The reconstructed image is applied as input to acomputer 36 which stores the image in amass storage device 38 .

计算机36还经由控制台40从操作员处接收指令和扫描参数，控制台40具有某种形式的操作员界面，诸如键盘、鼠标、声控控制器或者任何其它适合的输入装置。相关的显示器42允许操作员观察重构的图像和来自计算机36的其它数据。操作员提供的指令和参数由计算机36用于提供控制信号和信息给DAS32、x射线控制器28和台架电动机控制器30。此外，计算机36操作工作台电动机控制器44，控制电动机化的工作台46来定位病人22和台架12。具体讲，工作台46将病人22整体或者部分移动通过图1的台架开口48。Thecomputer 36 also receives instructions and scanning parameters from an operator via aconsole 40 having some form of operator interface, such as a keyboard, mouse, voice-activated controller, or any other suitable input device. An associateddisplay 42 allows the operator to view the reconstructed images and other data from thecomputer 36 . Operator supplied instructions and parameters are used bycomputer 36 to provide control signals and information toDAS 32 ,x-ray controller 28 andgantry motor controller 30 . In addition,computer 36 operatestable motor controller 44 to control motorized table 46 to position patient 22 and table 12 . In particular, table 46 moves patient 22 in whole or in part through table opening 48 of FIG. 1 .

如图3所示，检测器组件18包括导轨17，准直叶片或板19置于其间。放置板19以在x射线束碰撞到例如位于检测器组件18上的图4的检测器之前对其进行准直。在一个实施例中，检测器组件18包括57个检测器20，每个检测器20具有像素元50的64×16的阵列规格。结果，检测器组件18具有64行和912列(16x57个检测器)，这允许随台架12的每次旋转收集64个同时的数据层。As shown in Figure 3, thedetector assembly 18 includesrails 17 between which collimating blades orplates 19 are positioned.Plate 19 is placed to collimate the x-ray beam before it hits a detector such as that of FIG. 4 located ondetector assembly 18 . In one embodiment,detector assembly 18 includes 57detectors 20 each having a 64×16 array format ofpixel elements 50 . As a result, thedetector assembly 18 has 64 rows and 912 columns (16x57 detectors), which allows 64 simultaneous data layers to be collected with each rotation of thegantry 12 .

参考图4，检测器20包括DAS32，每个检测器20包括布置在包装51中的多个检测器元件50。检测器20包括相对于检测器元件50设置在包装51中的引脚52。包装51放置在具有多个二极管59的背光二极管阵列53上。背光二极管阵列53接着放置在多层基底54上。间隔物55放置在多层基底54上。检测器元件50光耦合到背光二极管阵列53，背光二极管阵列53接着电耦接到多层基底54。柔性电路56连接到多层基板54的表面57以及DAS32。检测器20通过使用引脚52放置在检测器组件18中。Referring to FIG. 4 ,detectors 20 includeDAS 32 , eachdetector 20 including a plurality ofdetector elements 50 arranged in a package 51 .Detector 20 includespins 52 disposed in package 51 relative todetector element 50 . The package 51 is placed on abacklit diode array 53 having a plurality ofdiodes 59 .Backlight diode array 53 is then placed onmultilayer substrate 54 . Aspacer 55 is placed on themultilayer substrate 54 .Detector element 50 is optically coupled tobacklit diode array 53 , which is in turn electrically coupled tomultilayer substrate 54 .Flexible circuit 56 is attached to surface 57 ofmultilayer substrate 54 and toDAS 32 .Detector 20 is placed indetector assembly 18 using pins 52 .

在一个实施例的操作中，撞击在检测器组件50中的x射线生成穿过包装51的光子，从而产生在背光二极管阵列53中的二极管上检测到的模拟信号。该产生的模拟信号传送通过多层基板54，通过柔性电路56，到DAS32，该模拟信号在其中求积分并被转换成数字信号。In operation of one embodiment, x-rays impinging ondetector assembly 50 generate photons that pass through package 51 , producing analog signals that are detected on the diodes inbacklight diode array 53 . The resulting analog signal is transmitted throughmultilayer substrate 54, throughflex circuit 56, toDAS 32 where it is integrated and converted to a digital signal.

或者每个检测器20可以被设计为将射线能量直接转换成包含能量辨别或光子计数数据的电信号。这种检测器通常被称为“直接转换”器件。直接转换器件也可以相似地被配置为工作在积分模式。这种器件可以被称为可配置。在一优选实施例中，每个检测器20包括从CZT制作的半导体层。每个检测器20还包括连接到半导体层的多个金属化阳极。如后面将描述的，这种检测器20其上具有多个比较器的电路，这可以减少由于多个能量事件的积累引起的统计错误。Alternatively eachdetector 20 may be designed to convert radiation energy directly into an electrical signal containing energy discrimination or photon counting data. Such detectors are often referred to as "direct conversion" devices. Direct conversion devices can also be similarly configured to operate in integrating mode. Such devices may be referred to as configurable. In a preferred embodiment, eachdetector 20 comprises a semiconductor layer fabricated from CZT. Eachdetector 20 also includes a plurality of metallized anodes connected to the semiconductor layer. As will be described later, thisdetector 20 has a circuit with multiple comparators on it, which can reduce statistical errors due to the accumulation of multiple energy events.

现在参考图5，示出根据本发明一个实施例的CZT或直接转换检测器的一部分。检测器20由半导体层60定义，半导体层60具有多个电子的像素化的结构或者像素来定义多个检测器元件，阳极或触点62。该电子像素化是通过将电触点62的2D阵列64施加到直接转换材料的层60上来实现的。Referring now to FIG. 5, a portion of a CZT or direct conversion detector according to one embodiment of the present invention is shown. Thedetector 20 is defined by a semiconductor layer 60 having a plurality of electronic pixelated structures or pixels to define a plurality of detector elements, anodes or contacts 62 . This electronic pixelation is achieved by applying a 2D array 64 of electrical contacts 62 onto the layer 60 of direct conversion material.

检测器20包括连接到半导体层60的邻近的高压电极66。高压电极66连接到电源(未示出)，并且其被设计为在x射线检测过程中给半导体层60供电。本领域技术人员将意识到高压电极66应当相对薄以减少x射线吸收特性，并且，在一优选实施例中厚度为几百埃。在一个优选实施例中，高压电极66可以通过金属化工艺固定到半导体层60上。撞击半导体层60的x射线光子将在其中产生电荷，该电荷在一个或多个电触点62中收集，并且可以被读出到图2的DAS32。收集的电荷的幅度指示了产生该电荷的光子的能量。Thedetector 20 includes an adjacent high voltage electrode 66 connected to the semiconductor layer 60 . The high voltage electrode 66 is connected to a power source (not shown) and is designed to power the semiconductor layer 60 during x-ray inspection. Those skilled in the art will appreciate that the high voltage electrode 66 should be relatively thin to reduce x-ray absorbing properties and, in a preferred embodiment, is several hundred angstroms thick. In a preferred embodiment, the high voltage electrode 66 can be fixed on the semiconductor layer 60 by a metallization process. X-ray photons striking semiconductor layer 60 will generate a charge therein that is collected in one or more electrical contacts 62 and can be read out toDAS 32 of FIG. 2 . The magnitude of the collected charge is indicative of the energy of the photon that created that charge.

积分检测器或者在积分模式工作的光子计数检测器提供CT数值或Hounsfield值。另一方面，能量选择或者能量辨别CT系统可以提供与材料的原子数和密度相关的附加信息。该信息对于多种医疗临床应用可以是特别有用的，其中不同材料的CT数值可能相似但是原子数可能较为不同。例如，钙化的斑和碘对比增强的血液可能一起位于冠状动脉或其它组织中。如同本领域技术人员将意识到的，已知钙化的斑和碘对比增强的血液具有截然不同的原子数，但是在某种密度下这两种材料不能单独由CT数值区分。Integrating detectors or photon counting detectors operating in integrating mode provide CT values or Hounsfield values. On the other hand, energy selective or energy discriminative CT systems can provide additional information related to the atomic number and density of the material. This information can be particularly useful for a variety of medical clinical applications, where the CT values of different materials may be similar but the atomic numbers may be relatively different. For example, calcified plaques and iodine contrast-enhanced blood may be located together in coronary arteries or other tissues. As will be appreciated by those skilled in the art, it is known that calcified plaque and iodine contrast enhanced blood have distinct atomic numbers, but at a certain density the two materials cannot be distinguished by CT value alone.

由于与光子计数检测器相比积分检测器不同的饱和水平和增加的饱和阈值，光子计数检测器的饱和区域可能发生在低于能量积分检测器中发生饱和的通量水平。此外，即使可以将光子计数检测器配置为以积分模式工作，这种工作具有有限的动态范围并且可能不足以避免饱和。因此，可以在双源/双检测器布置中采用检测器类型的组合，以便用来自第二检测器的非饱和数据修补检测器的饱和区域，并保留最高的剂量使用。Due to the different saturation levels and increased saturation threshold of integrating detectors compared to photon counting detectors, saturation regions for photon counting detectors can occur at lower flux levels than saturation occurs in energy integrating detectors. Furthermore, even if a photon-counting detector could be configured to operate in integrating mode, such operation has limited dynamic range and may not be sufficient to avoid saturation. Therefore, a combination of detector types can be employed in a dual source/dual detector arrangement in order to patch up the saturated regions of the detector with non-saturated data from the second detector and preserve the highest dose usage.

参考图6，示出了根据本发明一个实施例的CT台架10的轴位图。台架12包括第一x射线源90和第二x射线源92。在该实施例中，第一检测器100在弧102上接收数据，以便接收通过第一视域(FOV)104的数据。第二检测器106在弧108上接收数据，以便接收通过第二FOVReferring to FIG. 6 , there is shown an axial view of aCT gantry 10 according to an embodiment of the present invention.Gantry 12 includes afirst x-ray source 90 and asecond x-ray source 92 . In this embodiment, afirst detector 100 receives data over anarc 102 to receive data through a first field of view (FOV) 104 .Second detector 106 receives data onarc 108 for reception through a second FOV

110的数据。在该实施例中，第二FOV110小于第一FOV104。然而，本领域技术人员将认识到取决于检测器100和106中实现的覆盖弧102和108，两个FOV104和110可以大小相同，或者第二FOV110可以大于第一FOV104。可变蝶形滤片112，114可以可选的放置在一个或两个x射线源90，92它们各自的检测器100，106之间。本领域技术人员将认识到具有例如高于光子计数检测器的饱和阈值的检测器，诸如积分检测器，可以不需要蝶形滤片。110 data. In this embodiment, thesecond FOV 110 is smaller than thefirst FOV 104 . However, those skilled in the art will recognize that depending on the coverage arcs 102 and 108 implemented in thedetectors 100 and 106 , bothFOVs 104 and 110 may be the same size, or thesecond FOV 110 may be larger than thefirst FOV 104 . Variable butterfly filters 112, 114 may optionally be placed between one or bothx-ray sources 90, 92 and theirrespective detectors 100, 106. Those skilled in the art will recognize that detectors, such as integrating detectors, having a saturation threshold, eg, higher than photon counting detectors, may not require a butterfly filter.

根据本发明的一个实施例，覆盖FOV104的检测器100是基于闪烁体的合计检测器，覆盖FOV110的第二检测器106是直接转换、光子计数检测器。由于两个检测器的饱和阈值不同，并且直接转换检测器中的饱和阈值趋向于为较低，直接转换检测器106的部分在给定的通量水平下容易饱和，不管是否存在蝶形滤片114。然而，由于积分检测器100增加的动态范围能力，检测器100将趋向于在相当的通量水平下也不饱和，从而提供可以用于修补FOV110中发生的检测器106的饱和区域的数据。According to one embodiment of the invention, thedetector 100 overlayingFOV 104 is a scintillator based summing detector and thesecond detector 106 overlayingFOV 110 is a direct conversion, photon counting detector. Since the saturation thresholds of the two detectors are different, and tend to be lower in direct conversion detectors, portions of thedirect conversion detector 106 tend to saturate at a given flux level, regardless of the presence of thebutterfly filter 114. However, due to the increased dynamic range capability of the integratingdetector 100, thedetector 100 will also tend not to saturate at comparable flux levels, providing data that can be used to repair the saturation region of thedetector 106 that occurs in theFOV 110.

换言之，当第二检测器106饱和时，由于第二检测器106对应的FOV110小于较大检测器100的FOV104，并且由于第一检测器100具有较高的通量能力，其中获得的数据可以用于校正否则的话在光子计数检测器106中丢失的数据。本领域技术人员将认识到从一个检测器100取得并修补到第二检测器106中的数据必须适当地配准，以计入获取数据的两个台架角度。In other words, when thesecond detector 106 is saturated, since the correspondingFOV 110 of thesecond detector 106 is smaller than theFOV 104 of thelarger detector 100, and because thefirst detector 100 has a higher throughput capability, the data obtained therein can be obtained with to correct data that would otherwise be lost in thephoton counting detector 106 . Those skilled in the art will recognize that data taken from onedetector 100 and inpainted into asecond detector 106 must be properly registered to account for the two gantry angles at which the data was taken.

现在参考图7，示出了根据本发明另一个实施例的CT台架10的轴位图。台架12包括第一x射线源190和第二x射线源192。在该实施例中，第一检测器200在弧202上接收数据，以便接收通过第一FOV204的数据。第二、分段弧检测器206在弧208上接收数据，以便接收通过第二FOV210的数据。在该实施例中，第一FOV204小于第二FOV210。然而，本领域技术人员将认识到取决于检测器200和206中实现的覆盖弧202和208，两个FOV204和210可以大小相同，或者第二FOV210可以小于第一FOV204。可变蝶形滤片212，214可以可选的放置在一个或两个x射线源190，192它们各自的检测器200，206之间。本领域技术人员将认识到具有例如高于光子计数检测器的饱和阈值的检测器，诸如积分检测器，可以不需要蝶形滤片。Referring now to FIG. 7 , an isometric view of aCT gantry 10 according to another embodiment of the present invention is shown.Gantry 12 includes afirst x-ray source 190 and asecond x-ray source 192 . In this embodiment,first detector 200 receives data onarc 202 to receive data throughfirst FOV 204 . Second, segmentedarc detector 206 receives data onarc 208 to receive data throughsecond FOV 210 . In this embodiment,first FOV 204 is smaller thansecond FOV 210 . However, those skilled in the art will recognize that depending on the coverage arcs 202 and 208 implemented in thedetectors 200 and 206 , bothFOVs 204 and 210 may be the same size, or thesecond FOV 210 may be smaller than thefirst FOV 204 . Variable butterfly filters 212, 214 may optionally be placed between one or bothx-ray sources 190, 192 and theirrespective detectors 200, 206. Those skilled in the art will recognize that detectors, such as integrating detectors, having a saturation threshold, eg, higher than photon counting detectors, may not require a butterfly filter.

在一个实施例中，检测器200可以是基于闪烁体的积分检测器，或者可配置为工作在积分或者光子计数模式之一的光子计数检测器。另一方面，分段弧检测器206具有第一部分220和第二部分222，223。根据本发明一个实施例，第一部分220配置为工作在与第二部分222，223不同的处理模式。以这种方式，第一部分220可以是配置为工作在光子计数模式的可配置能量辨别检测器部分，第二部分222，223可以是基于闪烁体的积分检测器，或配置为工作在积分模式的可配置能量辨别检测器部分。这样，检测器206可以具有由在第二FOV210中包含的第一部分220限定的二次FOV230。尽管二次FOV230显示为直径小于对应于第一检测器200的FOV204，但本领域技术人员将认识到FOV204，230同样可以具有相若的直径或者二次FOV230直径可以小于FOV204的直径。In one embodiment,detector 200 may be a scintillator-based integrating detector, or may be configured as a photon counting detector operating in one of an integrating or photon counting mode. On the other hand, thesegmented arc detector 206 has afirst portion 220 and asecond portion 222 , 223 . According to an embodiment of the present invention, thefirst part 220 is configured to work in a different processing mode than the second part 222,223. In this manner, thefirst section 220 may be a configurable energy-discriminating detector section configured to operate in photon counting mode, and thesecond sections 222, 223 may be scintillator-based integrating detectors, or configurable to operate in integrating mode. Configurable energy discriminative detector section. As such, thedetector 206 may have asecondary FOV 230 defined by thefirst portion 220 contained within thesecond FOV 210 . Althoughsecondary FOV 230 is shown as being smaller in diameter thanFOV 204 corresponding tofirst detector 200 , those skilled in the art will recognize thatFOVs 204 , 230 could also be of similar diameter or thatsecondary FOV 230 could be smaller in diameter thanFOV 204 .

由于检测器在部分220中的饱和阈值不同于检测器在部分222，223中的饱和阈值，第一部分220的部分容易在低于检测器200的给定的通量水平下饱和，不管是否存在蝶形滤片212。然而，由于检测器200增加的动态范围能力，检测器200将趋向于在相若的通量水平下也不饱和，从而提供可以用于修补FOV230中发生的检测器部分220的饱和区域的数据。Since the saturation threshold of the detector insection 220 is different from the saturation threshold of the detectors insections 222, 223, sections of thefirst section 220 tend to saturate at a given flux level belowdetector 200, regardless of the presence or absence ofShaped filter disc 212. However, due to the increased dynamic range capability ofdetector 200 ,detector 200 will also tend not to saturate at comparable flux levels, providing data that can be used to repair the saturation regions ofdetector portion 220 that occur inFOV 230 .

换言之，当第一部分220中数据饱和时，检测器200中的数据可以用于校正否则的话在光子计数部分220中丢失的数据。本领域技术人员将认识到从检测器200取得并修补到第一检测器部分220中的数据必须适当地配准，以计入获取数据的两个台架角度。In other words, when the data in thefirst section 220 is saturated, the data in thedetector 200 can be used to correct data that would otherwise be lost in thephoton counting section 220 . Those skilled in the art will recognize that data taken fromdetector 200 and inpainted intofirst detector section 220 must be properly registered to account for the two gantry angles at which the data was taken.

在这里描述的实施例中，数据的校正可以通过使用迭代重构技术完成。在该技术中，通过对所研究的目标的图像进行初始猜测或者尝试来开始饱和数据的校正。前面的方法使用系统模型来设计尝试图像，以便获得预期的数据。预期的数据与实际测量的数据之间的差异产生用于调整尝试图像的误差。重复该过程以便使预期的数据更好地匹配测量的数据，直到达到精度或者迭代次数的限制。In the embodiments described herein, correction of the data may be accomplished using iterative reconstruction techniques. In this technique, the correction of saturation data begins by making an initial guess or attempt on an image of the object of interest. The preceding methods use a system model to design trial images in order to obtain expected data. The difference between the expected data and the actual measured data creates an error for adjusting the attempted image. This process is repeated to better match the expected data to the measured data, until the limit of accuracy or number of iterations is reached.

在这里描述的实施例中，数据修补可以通过计入各检测器之间台架角度的差异并相应地内插来进行。对于轴向扫描，通过基于获取的数据是否偏移了整数数量的视图来计入台架角度中的差异，重建(rebin)数据。如果两个检测器偏移了整数数量的视图，那么通过简单的将数据集偏移该整数数量的偏移视图来执行重建(rebinning)。如果两个检测器没有偏移整数数量的视图，那么将来自一个检测器的在一组台架角度上的数据线性插值到第二检测器的台架角度集。In the embodiments described here, data inpainting can be performed by accounting for differences in gantry angles between detectors and interpolating accordingly. For axial scans, the data were rebinned by accounting for differences in gantry angle based on whether the acquired data was shifted by an integer number of views. If two detectors are offset by an integer number of views, then rebinning is performed by simply offsetting the dataset by that integer number of offset views. If the two detectors do not have views offset by an integer amount, then the data from one detector over one set of gantry angles is linearly interpolated to the second detector's set of gantry angles.

对于螺旋扫描，需要更精细的内插。即，当一源/检测器子系统在时间T处于第一角度A时，那么直到时间T+delta第二源/检测器子系统不会到达角度A。在该时间间隔delta内，病人被移动，从而通过该病人的视图不是等价的(由于它们是在轴向扫描中)。数据实际上是角度和沿Z轴的病人位置的二维离散集合的函数。从而，内插必须计入螺旋扫描中检测器的视位(view position)和沿Z轴的病人位置。For helical scans, finer interpolation is required. That is, when one source/detector subsystem is at a first angle A at time T, then the second source/detector subsystem will not reach angle A until time T+delta. During this time interval delta, the patient is moved so that the views through the patient are not equivalent (since they are in the axial scan). The data is actually a two-dimensional discrete set of functions of angle and patient position along the Z axis. Thus, the interpolation must take into account the view position of the detector in the helical scan and the patient's position along the Z axis.

现在参考图8，包裹/行李检查系统510包括可旋转台架512，可旋转台架512中具有开口514，包裹和行李可以通过该开口。可旋转台架512包含高频电磁能量源516以及检测器组件518，检测器组件518具有由类似于图4或图5中所示的闪烁体单元的闪烁体单元构成的闪烁体阵列。还提供传送机系统520，其包括由结构524支撑的传送带522，以便自动和连续的将包裹或行李526传过开口514以进行扫描。目标526由传送带522馈送通过开口514，接着获取成像数据，传送带522以受控和连续的方式从开口514移走包裹526。结果，邮政检查员、行李处理员以及其它安全人员可以非侵入地检查包裹526的内容，查找爆炸物、刀具、枪支、违禁品等。Referring now to FIG. 8, a package/baggage inspection system 510 includes arotatable gantry 512 having anopening 514 therein through which packages and luggage may pass. Therotatable gantry 512 contains a source of high frequencyelectromagnetic energy 516 and adetector assembly 518 having a scintillator array comprised of scintillator units similar to those shown in FIG. 4 or FIG. 5 . Aconveyor system 520 is also provided which includes aconveyor belt 522 supported by astructure 524 to automatically and continuously pass packages orluggage 526 throughopening 514 for scanning.Objects 526 are fed throughopening 514 byconveyor belt 522, which removespackages 526 from opening 514 in a controlled and continuous manner prior to acquiring imaging data. As a result, postal inspectors, baggage handlers, and other security personnel can non-intrusively inspect the contents ofpackage 526 for explosives, knives, firearms, contraband, and the like.

因此，根据本发明的一个实施例，一种CT成像系统包括可旋转台架，具有接收要扫描的目标物体的开口；第一x射线发射源，连接到所述可旋转台架并且配置为朝目标物体发射x射线；以及第二x射线发射源，连接到所述可旋转台架并且配置为朝目标物体发射x射线。第一检测器配置为接收从第一x射线发射源发射的x射线，第二检测器配置为接收从第二x射线发射源发射的x射线。第一检测器的第一部分配置为工作在积分模式，第二检测器的第一部分配置为工作在至少光子计数模式。Therefore, according to one embodiment of the present invention, a CT imaging system includes a rotatable gantry having an opening for receiving a target object to be scanned; a first x-ray emitting source connected to the rotatable gantry and configured to a target object emitting x-rays; and a second x-ray emitting source coupled to the rotatable gantry and configured to emit x-rays toward the target object. The first detector is configured to receive x-rays emitted from the first x-ray emitting source and the second detector is configured to receive x-rays emitted from the second x-ray emitting source. A first portion of the first detector is configured to operate in an integrating mode and a first portion of the second detector is configured to operate in at least a photon counting mode.

根据本发明的另一实施例，一种x射线成像的方法包括，在第一检测器阵列的第一部分中接收x射线，所述x射线从第一x射线源发出穿过成像区域的至少一部分，以及在第二检测器阵列的第一部分中接收x射线，所述x射线从第二x射线源发出穿过成像区域的至少一部分。该方法还包括，以积分模式操作第一检测器阵列的第一部分，以从接收的x射线生成第一组数据，以光子计数模式操作第二检测器阵列的第一部分，以从接收的x射线生成第二组数据，以及使用第一和第二组数据生成图像。According to another embodiment of the present invention, a method of x-ray imaging includes receiving x-rays in a first portion of a first detector array, the x-rays being emitted from a first x-ray source through at least a portion of an imaging region , and receiving x-rays in the first portion of the second detector array, the x-rays being emitted from the second x-ray source through at least a portion of the imaging region. The method also includes operating a first portion of the first detector array in an integrating mode to generate a first set of data from received x-rays and operating a first portion of a second detector array in a photon counting mode to generate a first set of data from received x-rays A second set of data is generated, and an image is generated using the first and second sets of data.

根据本发明的再一实施例，一种CT成像系统包括台架，配置为绕目标物体旋转；以及一对源，连接到所述台架并配置为朝目标物体发出高频电磁辐射。第一检测器阵列模块配置为接收从该对源的第一源发出并穿过物体的高频电磁辐射，第二检测器阵列模块配置为接收从该对源的第二源发出并穿过物体的高频电磁辐射。第一检测器阵列模块配置为工作在至少积分模式，第二检测器阵列模块配置为工作在至少光子计数模式。According to yet another embodiment of the present invention, a CT imaging system includes a gantry configured to rotate about a target object; and a pair of sources connected to the gantry and configured to emit high frequency electromagnetic radiation toward the target object. The first detector array module is configured to receive high frequency electromagnetic radiation emanating from the first source of the pair passing through the object and the second detector array module is configured to receive the high frequency electromagnetic radiation emanating from the second source of the pair passing through the object high-frequency electromagnetic radiation. The first detector array module is configured to work in at least the integration mode, and the second detector array module is configured to work in at least the photon counting mode.

已经借助优选实施例描述了本发明，但应理解除了明确表述的那些之外的等价物，替换和修改是可能的，并且在所附权利要求的范围内。The invention has been described by means of a preferred embodiment, but it should be understood that equivalents, substitutions and modifications other than those expressly stated are possible and within the scope of the appended claims.

10  计算断层扫描(CT)成像系统10 Computed Tomography (CT) Imaging System

12  台架12 benches

14x 射线源14x ray sources

16x 射线束16x ray beams

17  导轨17 guide rail

18  检测器组件或准直器18 detector assembly or collimator

19  准直叶片或板19 collimation blade or plate

20  多个检测器More than 20 detectors

32  数据获取系统(DAS)32 Data Acquisition System (DAS)

22  医疗病人22 medical patients

24  旋转中心24 center of rotation

26  控制机构26 control mechanism

28x 射线控制器28x ray controller

30  台架电动机控制器30 bench motor controller

34  图像重构器34 Image Refactorer

36  计算机36 computer

38  大容量存储装置38 mass storage device

40  操作员经由控制台40 Operators via console

42  相关的显示器42 Associated displays

44  工作台电动机控制器44 Table motor controller

46  电动机化的工作台46 Motorized Workbench

48  台架开口48 Bench opening

50  像素元50 pixels

51  包装51 packaging

52  引脚52 pins

53  背光二极管阵列53 backlight diode array

59  多个二极管59 multiple diodes

54  多层衬底54 Multilayer substrates

55  间隔物55 Spacers

56  柔性电路56 Flexible circuits

60  半导体层60 semiconductor layers

62  阳极或触点62 anode or contact

66  邻近的高压电极66 adjacent high voltage electrodes

90  第一x射线源90 first x-ray source

92  第二x射线源92 second x-ray source

100 第一检测器100 first detector

102 弧102 arc

104 第一视域(FOV)104 First View (FOV)

106 第二检测器106 Second detector

108 弧108 arc

110 第二FOV110 second FOV

112 可变蝶形滤片112 variable butterfly filter

114 可变蝶形滤片114 variable butterfly filter

190 第一x射线源190 first x-ray source

192 第二x射线源192 second x-ray source

200 第一检测器200 first detector

202 弧202 arc

204 第一FOV204 First FOV

206 第二、分段弧检测器206 Second, segmented arc detector

208 弧208 arc

210 第二FOV210 second FOV

212 可变蝶形滤片212 variable butterfly filter

214 可变蝶形滤片214 variable butterfly filter

220 第一部分220Part 1

222 第二部分222 Part Two

223 第二部分223 Part Two

230 二次FOV230 secondary FOV

510 包裹/行李检查系统510 Parcel/Baggage Inspection System

512 可旋转台架512 rotatable table

514 开口514 opening

516 高频电磁辐射源516 High-frequency electromagnetic radiation sources

518 检测器组件518 detector assembly

520 传送机系统520 Conveyor System

522 传送带522 conveyor belt

524 结构支撑的传送带524 Structurally Supported Conveyor Belts

526 包裹或行李526 Parcels or luggage

Claims (9)

1. a CT imaging system (10) comprising:

Rotatable gantry (12) has the opening (48) of the target object (22) that reception will scan;

The one x ray emission source (90,190) is connected to said rotatable gantry (12) and is configured to the ray towards target object (22) emission x;

The 2nd x ray emission source (92,192) is connected to said rotatable gantry (12) and is configured to the ray towards target object (22) emission x;

First detector (100,200) is configured to receive the x ray from an x ray emission source (90,190) emission; And

Second detector (106,206) is configured to receive the x ray from the emission of the 2nd x ray emission source (92,192);

Wherein the first of first detector (100,200) is configured to be operated in integral mode, and the first of second detector (106,220) is configured to be operated in photon counting mode at least,

Computer is programmed for use and proofreaies and correct the saturated data in second detector (106,206) from the unsaturation data of the first of first detector (100,200).

2. CT imaging system as claimed in claim 1 (10), wherein the first of first detector (100) comprises whole first detector.

3. CT imaging system as claimed in claim 2 (10), wherein the first of second detector comprises whole second detector (106).

4. CT imaging system as claimed in claim 2 (10), wherein second detector (106) has limited ken FOV (110), its ken FOV less than first detector (210).

5. CT imaging system as claimed in claim 2 (10), wherein the peak power capability that has of an x ray emission source (90) is greater than the peak power capability in the 2nd x ray emission source (92).

6. CT imaging system as claimed in claim 1 (10), wherein second detector (206) comprises direct transition detector, can be configured to be operated in integral mode or photon counting mode.

7. CT imaging system as claimed in claim 1 (10), wherein the second portion of second detector (222,223) is configured to be operated in integral mode at least.

8. CT imaging system as claimed in claim 7 (10), heart received the center x beam that sends from the 2nd x ray emission source (192) during wherein the first of second detector (220) was placed as.

9. CT imaging system as claimed in claim 1 (10); The second portion (222 of second detector wherein; 223) be configured to be operated in the arbitrary patterns in integral mode and the photon counting mode, and wherein the peak power capability that has of the 2nd x ray emission source (192) greater than the peak power capability in an x ray emission source (190).

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